Mice required for the 4 projects of this PPG will be bred and maintained by the Animal Core. The Core will arrange the purchase and transfer of breeder pairs for 5 developed strains: eNOS, nNOS, EC-SOD, NAD(P)H oxidase-p47/phox subunit, and D5-R. Colonies to support adult male mice of 8-14 weeks will be developed from the initial breeders. Heterozygous (+/-) mice will be bred to provide both homozygous (+/+) wild type and homozygous (-/-) deleted mice in the same litter, to maximize the genetic background of the control groups. The Core has in place a detailed plan that specifies the number of mice required to generated sufficient study animals. The Core will maintain a database of pertinent information that correlates to the ear tag identification number of each mouse. The Core will collect blood from weaning mice for genotyping, which will be performed fin the Molecular Core. The systolic blood pressure of each animal will be measured before and during placement of subcutaneous mini-pumps. Mini-pumps will contain either vehicle or angiotensin II (Ang II). 24 hour urine will be collected and analyzed for 8-isoprostane, lipid peroxidation, nitric oxide metabolites, and creatinine. The Core will also measure the conscious mean arterial blood pressure directly by radio telemetry in a subset of each single-gene deleted strain, before and during mini-pumps placement. The Core will provide technical support for each project in all areas relating to animals and analysis.